反应详情

温度

0 °C

To a solution of dimethyl carbonate (31.5 g, 350 mmol) in dry THF (600 mL) was added sodium hydride (14.4 g, 360 mmol) by portion at 0° C. The resulting mixture was stirred at 0° C. for 30 min and then was added a solution of 4,4-dimethylcyclohexanone (15 g, 119 mmol) in THF (150 mL) dropwise over 30 min. The resultant mixture was heated at 60° C.-80° C. for 3 h before cooled to room temperature. The reaction mixture was poured into saturated NaHCO3 solution and extracted with a mixture of 33% ethyl acetate in petroleum ether. The organic layer was washed with water, brine, dried over Na2SO4 and concentrated to give 26.5 g crude of methyl 2-hydroxy-5,5-dimethylcyclohex-1-enecarboxylate, which was used in next step without further purification. 1H NMR (DMSO-d6) δ 12.09 (s, 1H), 3.71 (s, 3H), 2.25-2.26 (m, 2H), 1.99 (s, 2H), 1.40-1.41 (m, 2H), 0.92 (s, 1H).

1. temperaturebefore cooled to room temperature
2. extractionextracted with a mixture of 33% ethyl acetate in petroleum ether
3. washThe organic layer was washed with water, brine
4. dry with materialdried over Na2SO4
5. concentrationconcentrated